id: "SA-08(08)" title: "Secure Evolvability" family: "SA" family_name: "System and Services Acquisition" sort_id: "sa-08.08" priority: "P1" implementation_level: "system" parent: "SA-08" enhancement: True


Statement

Implement the security design principle of secure evolvability in {{ insert: param, sa-08.08_odp }}.

Guidance

The principle of secure evolvability states that a system is developed to facilitate the maintenance of its security properties when there are changes to the system’s structure, interfaces, interconnections (i.e., system architecture), functionality, or configuration (i.e., security policy enforcement). Changes include a new, enhanced, or upgraded system capability; maintenance and sustainment activities; and reconfiguration. Although it is not possible to plan for every aspect of system evolution, system upgrades and changes can be anticipated by analyses of mission or business strategic direction, anticipated changes in the threat environment, and anticipated maintenance and sustainment needs. It is unrealistic to expect that complex systems remain secure in contexts not envisioned during development, whether such contexts are related to the operational environment or to usage. A system may be secure in some new contexts, but there is no guarantee that its emergent behavior will always be secure. It is easier to build trustworthiness into a system from the outset, and it follows that the sustainment of system trustworthiness requires planning for change as opposed to adapting in an ad hoc or non-methodical manner. The benefits of this principle include reduced vendor life cycle costs, reduced cost of ownership, improved system security, more effective management of security risk, and less risk uncertainty.

Assessment Objective

{{ insert: param, sa-08.08_odp }} implement the security design principle of secure evolvability.

System and services acquisition policy

procedures addressing the security design principle of secure evolvability used in the specification, design, development, implementation, and modification of the system

system design documentation

security and privacy requirements and specifications for the system

system security and privacy architecture

system security plan

other relevant documents or records

Organizational personnel with the responsibility for determining system security and privacy requirements

organizational personnel with system specification, design, development, implementation, and modification responsibilities

system developers

organizational personnel with information security responsibilities

Organizational processes for applying the security design principle of secure evolvability in system specification, design, development, implementation, and modification

mechanisms supporting the application of the security design principle of secure evolvability in system specification, design, development, implementation, and modification